57 Chevy Panel w/roof issues

[Highsider]

Newly acquired and I need a few opinions on the roof. Strange things have been done by the previous owner, including installing a large electric moon roof over the driver’s seat. I am scared to open it, in case the rubber seal is toast and I don’t mind sealing it in. Worse, I am guessing they installed a 14” crank-up rv roof vent over what was a pair of passenger seats. They tried to fill in the hole with putty. I am not an experienced body-man, but I don’t mind doing some grinding, putty, sanding and priming.

This truck is NOT going to be a show truck, but one idea was to do what it takes to make the roof completely done, in case eventually the rest of the truck ever gets finished.